fix(plugins): remove key if no plugins left (#2179)

Author: weisdd

controllers/controller_shared.go

@@ -203,13 +203,24 @@ func updatePluginConfigMap(cm *corev1.ConfigMap, value []byte, key string, depre
 	}
 
 	// TODO: temporary solution that is used to migrate to a new naming scheme, can be deprecated later
-	_, ok := cm.BinaryData[deprecatedKey]
-	if ok {
+	if _, ok := cm.BinaryData[deprecatedKey]; ok {
 		delete(cm.BinaryData, deprecatedKey)
 
 		isUpdated = true
 	}
 
+	// Delete the key if no plugins left
+	if len(value) == 0 {
+		if _, ok := cm.BinaryData[key]; ok {
+			{
+				delete(cm.BinaryData, key)
+				isUpdated = true // nolint:wsl_v5
+
+				return
+			}
+		}
+	}
+
 	if !bytes.Equal(value, cm.BinaryData[key]) {
 		cm.BinaryData[key] = value
 		isUpdated = true
@@ -235,9 +246,15 @@ func ReconcilePlugins(ctx context.Context, k8sClient client.Client, scheme *runt
 	// when we fetch the actual contents of the ConfigMap using k8sClient, so we need to set it here again
 	controllerutil.SetControllerReference(grafana, cm, scheme) //nolint:errcheck
 
-	val, err := json.Marshal(plugins.Sanitize())
-	if err != nil {
-		return err
+	val := []byte{}
+
+	// Just in case we have some broken plugins, better to assess length of the sanitized list, not the original one
+	sanitized := plugins.Sanitize()
+	if len(sanitized) > 0 {
+		val, err = json.Marshal(sanitized)
+		if err != nil {
+			return err
+		}
 	}
 
 	isUpdated := updatePluginConfigMap(cm, val, cmKey, cmDeprecatedKey)

controllers/controller_shared_test.go

@@ -373,6 +373,36 @@ func TestUpdatePluginConfigMap(t *testing.T) {
 				},
 			},
 		},
+		{
+			name: "removed plugin (nil)",
+			cm: &corev1.ConfigMap{
+				BinaryData: map[string][]byte{
+					"a": []byte("1"),
+				},
+			},
+			value:         nil,
+			key:           "a",
+			deprecatedKey: "b",
+			want:          true,
+			wantCM: &corev1.ConfigMap{
+				BinaryData: map[string][]byte{},
+			},
+		},
+		{
+			name: "removed plugin (empty slice)",
+			cm: &corev1.ConfigMap{
+				BinaryData: map[string][]byte{
+					"a": []byte("1"),
+				},
+			},
+			value:         []byte{},
+			key:           "a",
+			deprecatedKey: "b",
+			want:          true,
+			wantCM: &corev1.ConfigMap{
+				BinaryData: map[string][]byte{},
+			},
+		},
 	}
 
 	for _, tt := range tests {